Piston ring



Feb. zo, 1940. W, H- LONGABAUGH 2,191,023

PISTON RING Filed June 16, 1937 Y 45 tacting sides 3 of the segments are formed with and the assembled ring be sprung into the ring 45 PatentedFeb. 2.0, 1940 UNITED STATES PATENT OFFICE- PISTON RING William H. Longabaugh, Baltimore, Md., assignor to Revere Copper and Brass Incorporated, Rome, N. Y., a corporation of Maryland Application June v1e, 1937, serial No. 148,531 'z claims. (cl. soo- 28) My invention relates to lpiston rings, particuseat on the walls of the cylinder, and for exl larly, but not exclusively, those for locomotive panding it laterally to cause its opposite sides 5 and marine enginesand other engines or pumps to contact with the opposite side walls 1 of the havingV cylinder bores of large diameter. ring groove, is provided a split spring ring hav- The invention has among its objects the provllng, -in radial cross-section, a U-shaped portion 5 sion of an improved segmental ring in which the I9, the legs 2| of which portion converge as they segments will be held in assembled relation and extend away from the bend of the U. At the the ring expanded radially against the cylinder' ends ofthe legs 2| opposite the bend of the U walls and laterally against the opposite walls of the ring is formed to provide flanges 23 which the .ring groove in the piston, the rings being contact with the inner peripheral faces of the se'g- 10 especially applicable in situations where the cyl ments. Owing to the flanges 23 engaging the inder is not truly cylindrical, `and the invention' inner peripheral faces of the segments the split particularly lending itself to the use of rings spring ring acts to expand the ring radially; and formed of copper-base alloys or other metals subthe U-shaped portion i9 of the split spring ring,

ject to breakage. being under compression when the ring is assem- 15 The invention will be best understood from the bled with the piston, tends to force the two anfollowing description when read in the light of nuli away from each other so as to expand the the accompanying drawing of an embodiment ring laterally. It will also be observed that when of the invention, while the scope of the inventhe ring is assembled with the piston, as illustion will be more, particularly pointed out in the trated in Fig. 4, the U-shaped portion of the 20 appended claims. 4spring holds the segments in assembled relation, In the drawing: so that if one should break the broken portion Fig. lisa plan of aring constructed according would still be heldin the ring groove in the to the invention; piston. Fig. 2 is a section on the line 2-2 of Fig. 1; The ring may be assembled with the piston by 25 Fig. 3 is a section on the line 3 3 of Fig. 1; placing the split spring ring in the ring groove and and then snapping the segments into the ring Fig. 4 is a fragment of a radial section of a groove into engagement with the U-shaped porcylinder and4 cooperating piston having the imtion of the spring ring. Preferably an opposite proved piston rings. pair of the segments are positively united to the 30 Referring to the drawing, the ring illustrated spring ring in any convenient manner before the is formed of a plurality of elongated arcuate segpistn ring is placed in the ring groove so as to ments l arranged side by side and end to end prevent the two annuli from rotating relative to to form a pair of annuli having contactingl each other. 'I'his may be done, for example, by sides-3, the remote sides 5 of the annuli tting inserting a pin 25 in aligned perforations formed 35 the opposite side walls 1 of the ring groove formed in these pairs of segments and the spring ring. in the piston (9, and the outer circumferential After the spring ring and these segments are infaces IU' of the annuli contacting with the inteserted in the ring groove the remaining segments rior-walls Il of the cylinder. As shown, the pormay be Vsnapped into the ring groove into en- 40 tions of the segments projecting from the ring gagement with the U-shaped portion of the 40 groove in the piston are formed with flanges I3 spring ring. However, if desired. and especially Vto provide a more extensive surfacefor contact when a laterally stiff spring ring is employed,

Awith the walls of the cylinder. the segments may be assembled with the spring l `Asillustrated, the lower portions of the conring before entering the ring in the ring groove grooves or recesses I5 extending throughout the groove in the usual manner. lengths of the segments so as to form in the as- The segments preferably are made by extrudsembled ringa circumferential groove or recess ing a copper-base alloy to form rods having the extending inwardly from the inner periphery of cross-section of the segments, and then bending the ring.- 'Ihe segments shown are so formed' lengths of these rods to curvilinear shape to form 50 -that the side Walls t1 of this circumferential the segments, after which the ends ofthe seggroove diverge as 4they extend inwardly from the ments are finished. It will be noted that the inner circumference of the ring toward its outer cross-section of the segnents is such as readily circumference. to permit this method of fabrication. If desired,\ For expanding the ring radially to cause it to however, the segments may be forged from rolled. 55

turned from elongated cast sleeves.

It will be understood that within the scope of the appended claims wide deviations may be made from the form of the invention described without departing tion. f

I claim:

1. A piston ring having, in combination, segmental elements. arranged side by side and. end to end to form al pair of opposed annuli, the adjacentfaces of the several segmental elements of each annulus being formed with recesses which in the assembled ring cooperate to form a groove having reentrant side wallsopening on the inner periphery of the ring, and a laterally expandible ring member `in said groove cooperating with and retained in said groove by the reentrantside walls thereof and'acting to urge said annuli laterally away from each other, whichA ring member is also expandible radially of the ring, said ring member and segmental elements having cooperating engaging transverse portions for causing said member to expand the ring radially.

2. A ring according to cl'aim 1 in which the laterally and radially expandible member is formed with oppositely extending iiange porfrom the spirit of the inventions at the exterior of the groove formed by the recesses in the segmental elements, which iiange portions engage with Ithe inner peripheral face portions of the segmental elements. I

3. The combination with a piston having a piston ring groove, of segmental rings in said piston ring groove, the facing sides oi said rings each being formed with a groove which laterally of the ring has a reentrant side, a laterally and radially resilient ring having side portions received in said grooves of said segmental rings for expanding said segmentall rings radially and for urging them laterally away fromeach other against abutments operatively provided by the lateral sides of said piston ring groove, said side portions of said laterally and radially resilient ring being shaped to cooperate with the reentrant sides 'of said grooves in said segmental rings for holding them and their segments in assembled relation in said piston ring groove.

' 4. A piston ring having, in combination, seg- 'mental elements arranged side by side and end to end to form a. pair of contiguous annullijthe adjacent faces of the several segmental elements of each annuli being formed with recesses which in the assembled ring cooperate to form a groove havingreentrant side walls opening on the inner 2,191,025 or extruded, round rods, or they may be ct and periphery of the ring, a ring member in said groove cooperating with and retained 4in said groove by the reentrant side walls thereof, said ring member being radially expansible, and said ring member and segmental elements having cooperating engaging transverse portions at the exterior oi said groove for expanding said ring radially.

5. A lpiston ring having, in combination, segmental elements arranged side by side and end vto end to form a pair of opposed annuli; the opposed sides of said elements being formed with complementary recesses presenting, in the assembled ring, a groove which opens on. an inner peripheral surface of the ring and has opposite side walls which diverge from the inner toward the outer periphery of the ring; and a laterally expandible means in .said groove engaging with the side walls thereof for holding said segmental elements in assembled relation when the ring is assembled in a piston ring groove and for expanding the ring laterally, said means also being expandible radially of the ring, said means and segmental elements having cooperating engaging ransverse portions for causing said means to expand the ring radially.

6. A ring according to claim 5 in which the body ,portion of the laterally and radially expandible means is generally U-shaped in cross-section diametrically of the ring with the opposite legs of the U converging toward each other as they extend toward the open end of the U,

which open end faces the open end of the groove formed by the recesses in the segmental elements lwhen said groove is viewed in cross-section diametrically of the ring, said opposite legs of the U engaging with the opposite side Walls of said groove..

. A'1. A ring according to claim 5 in which the body portion of the laterally and radially expandlble meansis generally U-shaped in crosssection diametrically of the ring with the opposite legs of the U converging toward each other as they extend toward the open end of. the

- U, which open end faces the open end of the.' groove formed by the recesses in the segmental elements when said groove is viewed in crosssection diametrically of the ring, said opposite ving portions engaging said surfaces.

WILLIAM H. LONGABAUGH. 

